Malicious PDF — malware analysis report

Static analysis result for SHA-256 825c6b6b2681312d…

MALICIOUS

PDF

91.0 KB Created: 2021-10-06 05:06:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 22f305ec3db66aa56b61001b1cf88873 SHA-1: 3f0ada4d2d6277506ee5f77a4e61481a62fdd1e1 SHA-256: 825c6b6b2681312d738cee0d319aa419c928fa2e121c4e29da9910a0eaa78c84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm, with multiple URLs pointing to compromised WordPress sites and other domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links. ClamAV detection and the ML classifier strongly suggest malicious intent, likely to phish or redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/e083245afe75deb53dbce5542c1ec409/dukekigipav.pdf In PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/supebanaguv.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/5128335824.pdfIn PDF document text
    • http://sinhorelli.com/userfiles/file/wotuloziwoluwuzuzodowakoj.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/161357eba2f7d2---parafivukosepulalekatubi.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613e4587a15da---jiziwosebirefexipafir.pdfIn PDF document text
    • https://mayxaydunghoangphuc.com/userfiles/files/wulemurop.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/p7hu415bgo88e25hnj644efijd/94984805631.pdfIn PDF document text
    • http://hotelborgodeipoeti.com/userfiles/files/94243513014.pdfIn PDF document text
    • http://capri.lt/userfiles/files/84675292212.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615ce13e81bc3---2841815002.pdfIn PDF document text
    • https://taflanelektronik.com/img/userfiles/file/44165676619.pdfIn PDF document text
    • http://shceping.com/upFile/photos/2021-9/file/jirumipigiziwapewimomiguw.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/47083766404.pdfIn PDF document text
    • https://johanbjerke.se/userfiles/file/bojimutozixaxexumikuri.pdfIn PDF document text
    • http://debrecen.varosom.hu/userfiles/files/86025002703.pdfIn PDF document text
    • https://kaemsp.org/upload/editor/file/kasab.pdfIn PDF document text
    • https://needlugs.com/userfiles/files/89881871633.pdfIn PDF document text
    • http://hermanosgolbano.com/admin/fckeditor/editor/filemanager/connectors/phpfile/86514914097.pdfIn PDF document text
    • http://tydafa.com/dafa/uploadfiles/20210908001806.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/161402a240fcae---65708944808.pdfIn PDF document text
    • https://ssmavidiyar.com/public/content-images/files/rezofabagojuzo.pdfIn PDF document text
    • https://lanjutpt1.com/contents/files/ripupapuvegajeran.pdfIn PDF document text
    • http://bacsiha.com/public/ckfinder/userfiles/files/9944470008.pdfIn PDF document text
    • https://almentispharma.com/ckfinder/userfiles/files/jinopewux.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/xokibakexekopudomur.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f26fb5ea55---99639754516.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=section+136+road+traffic+actPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA32 19780 bytes
SHA-256: a97553ea5c3f7de18a60fd4e81f9d6dd635e84e4bbad46440843ae0b81c5d0de
font_01_sfnt_off00012d5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D5F 10724 bytes
SHA-256: 8cb8014317e3aa068a2f20081873c619725392c70d8a55a9444666b5dc98f352
font_02_sfnt_off00014639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14639 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1